1. Technical Field
This application relates to a surgical stapling device for applying staples to tissue. More particularly, this application relates to a surgical stapling device having a single use loading unit (“SULU”) including a tool member for applying linear rows of staples to tissue and concurrently incising the tissue between the linear rows of staples.
2. Background of Related Art
Surgical devices for grasping or clamping tissue between opposed jaw structure of a tool assembly and thereafter fastening the clamped tissue are well known in the art. These devices may include a knife for incising the fastened tissue. The fasteners are typically in the form of surgical staples but two part fasteners formed of a material suitable for surgical use are also well known.
Typically, the tool member includes a staple cartridge which houses a plurality of staples arranged in at least two laterally spaced rows and an anvil which includes a plurality of staple forming pockets for receiving and forming staple legs of the staples as the staples are driven from the cartridge. Generally, the stapling operation is effected by a drive member that advances cam wedges longitudinally through the staple cartridge, with the cam wedges acting upon staple pushers to sequentially eject the staples from the staple cartridge. A knife can travel between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples.
In laparoscopic and/or endoscopic surgical procedures, the surgical procedure is performed through a small incision or through a narrow cannula inserted through a small entrance wound in a patient. In conventional or open procedures, surgeons directly access an operative site. Because of reduced patient trauma, shortened patient recovery periods and substantial reduction in overall cost, endoscopic procedures are preferred over open procedures. In order to address the specific needs of endoscopic and/or laparoscopic surgical procedures, endoscopic surgical stapling devices have been developed which provide a surgeon with easier access to the operative site. Typically, these stapling devices include an articulatable tool member which is supported adjacent to the distal end of the stapling device. The tool member can be selectively manipulated to allow a surgeon to manipulate a tool assembly in a confined space.
Tyco Healthcare Group, LP has manufactured and marketed articulatable endoscopic stapling instruments such as the MULTIFIRE ENDO GIA *30 and MULTIFIRE ENDO GIA *60 for several years. These instruments include a disposable loading unit (“DLU”) or single use loading unit (“SULU”) which includes a tool assembly, a proximal body portion and a mounting assembly for securing the tool assembly to the proximal body portion. These instruments have provided significant clinical benefits to the field of endoscopic surgery. Nonetheless, improvements in the area of reducing cost and complexity of manufacture are desirable.
In making improvements or modifications to the current instruments, it would be highly desirable not to sacrifice any of the important benefits of the MULTIFIRE ENDO GIA * 30 and 60 instruments as compared to other commercially available products. For example, any improvement should advantageously provide a fresh knife blade for each firing of the instrument and permit operation of the instrument with multiple size disposable loading units (DLU's).